Equipressure power generating plant and method of operating same



Feb. 22, 1955 E* MERcxER 2,702,453

EQUIPREssURE PONER GENERATING PLANT AND METHOD OP OPERATING SAME LLNJELUMNIUN 1f 15.7 l l 42 1 W l gl 155 l f5 l C- f j 37 l l ZUJJCOMPRE- l? l5 T b h-l@ MIM 5f, 21

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E. MERCIER EQUIPRESSURE POWER GENERATING PLANT AND METHOD OF OPERATING SAME Original Filed July 9, 1949 2 Sheets-Sheet 2 [273 21a-(f i271 275 :55 gz( am 265271 /Zl 247 2 Z ZQ-l si LE Z55 757 il im CONTROL,-

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GAS TURBINE Ms; lle/'aff United States Patent() EQUIPRESSURE PoWER GENERATINQ PLAN-'r AND METHOD oF oPERAriNG SAME- Ernest Mercier, Paris, France, assignor, by mes'ne-assgnments, to Mercier Development Corp., New' York, N; Y., a corporation of NewYork 17 Claims.' (Cl. Gli-39.18)

This invention relates to apparatus for the-development of power from fluid pressuremedia under pressures substantially above atmospheric pressure: The invention in particular relates to the development of power in prime movers by utilizing at least two fluids under pressure to develop power respectively in the-prime movers iconcomitantly with reduction of the pressure of theseuids.

ln a particular aspect the invention relates to the' conf trol-of the delivery of the uids tothe respective'prime movers in response to variations inthe pressures-of these: fluids with respect to eachw other so1as1to maintain' the pressures of the uids in a predetermined relation'.-

l'nmy copending application Serial No. 103,893, tiledli July 9, 1949, now Patent No. 2-,547,135,issued April- 3, 1951, of which the present application is a division-,-

l 'have disclosed and claimed a vapor generatorandthe* method ofoperating such a generator in which a vaporgeneratingt element is enclosedwithi'nacombustion chamber wherein the combustion gases are-maintained ata high pressure which approximates the pressure' of the vapor generated in the vapor generating element, means being provided for controlling. the supply of f'eland the delivery of a combustion supporting gas tov the'chamber so as tomaintain thelpressure ofthe combustion gasesV within the chamber in a predetermined Vrelation `to the pressure of the generated vapor.

As disclosed also in this prior application Serial No. 103,893, the desired predetermined relation off the pres'- suresof the combustionV gases and the vapor generated may be-maintained bycontrolliiig-theWithdrawal ofthe' vapor and of the combustion' gases from the-vapor generating element andromthe combustion chamber in response to variations from' ay predetermined diiererice' between the pressure of the vapori relative to the pressure:

of the combustion gases, Various means* are-disclosedinrthe prior application-for' controlling the combustion of the'fuel and the pressure of the-gases within the combustion chamber to secure and maintain thisdesired pre'J determined relation of the p'res'siires'l ofr the generated vapor and of the combustion gases. A differential de-y vice responsive to the pressure' of the geiier'atednvapor and to the pressure of the combustion-gases 'is utilizedv to actuate the different control means asdisclosed inl theV application Serial No. 103,893.

The present invention relates-to' an aspect of the dis# closure of the earlier application in which the vapor withdrawn from the vapor generating element is deliveredto a-vapor utilizing prime mover and the combustion gases withdrawn from the combustionA chamberv are delivered to a gas utilizing primemover respectively for developing power in these prime movers from thevapor and from the combustion gases. Preferably, as dis-v closed' in the earlier application, the pressures of the' vaporso withdrawn andl of the combustion gases withdrawn from the combustion chamber are of the sa'me order or substantially equal, and these pressures may be of the degree, for example, of 80 to 120 atmospheres or higher. Moreover, the combustion gases mayl be" produced in the combustion chamber' at temperatures ordi narily developed by conventional combustion of fuels such" as oil, gas, powdered coalor composite'- or colloidalfuels, and the temperature of the combustion gases a'ftcr' delivering heat t'o the Vapor generating elements` for generation of the vapor may become reduced, for ex# ample, to 500 C. as the'gasesare discharged r`r'o`i'ii` the casing. These gases at substantially die'same pressure and temperature are' delivered tov the gas .utilizing prime' mover.' rlhus, without exceeding the temperatures which conventionally used materials may withstand, the gases at such elevated pressure and' temperature may b'e used= ina gas utilizing-prime mover with-'af highpressure drop' and a high temperature" drop to the pressure andtein; perature ofthe exhaust from the prime' mover to' the atmosphere.

rlhe vapor generated, ordinarily steam' from water,-y may be generatedr iiiVv thin Walled vapor generating* ele"` ments, as disclosed in my earlier application Serial No; 103,893 and in prior application Serial No; 7,586ylec'l February 1l, 1948,- now raterit Nol 2,o`l8,247, issedNov. 18, 1932,' since the pressure or such vapor mayvv b e or' the same order or equal to the pressure-ot" the c'oriibusuo'n" gases enveloping'the vapor generating elemeis'disposed" within theV combustion chamber. utilizing prime mover which' may receivethe vapor at;

substantially the same pre'ssure'a't which it is generated" in the vapor generating element ii'iay bey or' conve tional'construction` capable or utilizing such'va'por' tode veioppower therefrom, tor example, steamat a p're's'sl'ireV or' 8U- to 120 atmospheres superlieated to any' desired degree:

and the'delivery or ow ofthe combustionl gases'to th gas utilizing prime mover are controlled in such a ma' neras to maintain the pressure' or" vap'r and ofA co" bustionV gases ina-pretieiermin'ed relation toeach' other.-

l-'rerer-ably, the means` for controlling tl'i'e delivery ow or the vap'r tothe vvapoi'f utilizing prime mover tor controlling-fthe delivery o`r now' or tll'e"` co gasesv to the' gas utilizing primenoveilboth'ar f' tively connected to` means responsiveto vritionslmabA predetermined' dirt'erence" between the' pressure of v'a'p'ora-nd the pressure lof the gases as "trley Vflow( towa'ilf the respective prime movers, that is, i'ii the pret rred embodiment, as they ow i"espe'ctively L le" generating element and Irom' the combustion chamber'.-

controll is'eirecied" by means, such' as a dinereiitial de ce'- connected so as to be responsive both to thepr'essiir i or' the generated'vaporandtdthe pressure of the corne' bustion gases, that is, responsive to" the ditrere'ice tween these pressures, whicheirectsz'iri i'i'cr'easein the corresponding' prime' mover when"th' 'p'res`s're 'of'v given` iuid'increases' with respect to thef'pressure' ofthe'y other liuidf. Concomitantly' the device etfec'tsdc'crea'sef or'A theV flow ofV the" other iiuidI to' the prime" mover rceivlng,` this other uid. Preferably, the' devieefutilized" for thus controlling the'delive'ries of the respective liiiids tothe 'prime movers cooperates witli a` conventional goverrior or speed regulating device which is` responsiveto the variations inspeed produced, for example, byv the load'carried' by the prime mven Other features and aspects of the invention be,k understood from the description of theA drawings to"fol' lov'vlinwhicli':`

Figi l show'sdiagrammaticallya power plant including a-st'eam generator arranged for' delivery of the'steam toastea'm turbine and or the combustion gases `to a gas:

delivering air to the' combustion chamber, aswell as for operating' the steam and gas'ow control means.l

In Fig. 1 is shown more or less diagrammatic'ally-` a" steam generator or equipressure boiler 1 having a casing 3 which may be' constructed as a steel cylinder having hernispherical upper andV lower' ends. A1: thel lower end ofthe casing 3 a flanged nozzle 10 isprovided-for the;

admission ofair and fori the insertionE-of'- the burners 11- rlne vapor or steam" por" within the casing 3. The air for combustion may be" delivered through the pipe 21 connected to the nozzle 10, this pipe being controlled' by a hand valve 23 and by control of the air compressor about to be described.

Within the casing 3 are disposed the steam generating elements or tubes 65 which in the embodiment shown in Fig. 1 are of serpentine form, the feed water being delivered to these tubes through the pipe 35 controlled by valve 37. The steam generated in the elements 65 may be discharged through the pipe 73. If desired, in accordance with the construction disclosed in my earlier application Serial No. 103,893, or by conventional means,

the steam generated in the tube 65 rmay be superheated,

to any desired superheat temperature before discharge through lthe pipe 73, "this discharge being controlled by thevalve 79 in pipe 73. The combustion gases afterpassing over the steam generating tubes 65 and over the superheaten'if such is provided. are discharged from the casing 3 through pipe 41 controlled by valve 43.

l The device for controlling the combustion within the combustion chamber comprises a cylinder 175 having a piston 176 movable therein. The space above the pis-` ton 176 is connected by pipe 177 to the steam outletpipe 7,3 so that the pressure of the generated Vsteam is brought from the/upper face of the piston 176. At ,the underside of the piston 17.6 is a spring 179 compressed upon increase of the steam pressure and etective to move the piston176 upwardly upon reduction of the-steam pressure. Increase and decrease of the steam pressure produce respectively downward and upward movement of the rod 181. To this rod is connected a ,horizontally extending armof a bellcrank 183 the downwardly eX- tending arm of whichis connected to the stem of valve 185 inserted in the fuel. supply pipe 17 leading to thev burner 11. Downward movement of the rod 181 moves thevalve disc 186 of the valve 185 toward its seat 187,`

thereby to decrease the ow of fuel to the burner 11.

Downward movement of the rod also effects movement-k of the bell crank 189, the horizontallv extending arm of which is connected to the rod 181 so that the downwardly extending arm ofrthis bell crankV connected to the stem of valve 191 moves the valve disc 192 toward the valve seat 193, the valve 191 being connected in pipe 195 which supplies fuel lto an internal combustion engine or a gas engine 197. The sunplv of fue] to this engine thusY 185 and the supplv of fuel to the engine 197 through the valve 191 will be decreased. thereby also decreasing the delivery of the compressed air to the combustion chamber because Vthe compressor 203 will be slowed` down. This simultaneous decrease of the supply of 4fuel and air to the lcombustion chamber decreases the heat release in the combustion chamber and. therefore, decreases the generation of steam and effects the reduction of the pressure of the steam as the steam is graduallv withdrawn from the steam` generating tubes 65 through thel pipe 205. Conversely, upon decrease of the steam pressure the pistou 176 is moved upwardly by the spring 179 and the supply of fuel to the combustion chamber and' to thev prime mover 197 is increased, the supply of compressed air from the compressor 203 correspondingly being increased. The release of heat in the combustion chamberrtherefore is increased to increase generation of steam in the steam generating tubes 65,'thereby to restore the pressure of the steam and correspondingly to reactuate the piston 176 downwardly to a' balanced position. In this manner the pressure of the'steam generated mav be maintained substantially constapt or within a predetermined degree of variation of such pressure.

vAs shown in Fig. 1 the steam generated in the steam generating tubes 65 is delivered by pipe 73 through valve 79 and through a pipe 205 to a steam turbine 207 for developing power therefrom. This turbine is controlled by a governor 209 actuating the governor valve 211 to control the speed of the turbine in response to variations l 4 f in the speed and of load in the conventional manner. The gases discharged from the gas space within the casing 3 of the steam generator are delivered through the valve 43 and the pipe 213 to a gas turbine 215 for developing power therefrom. The rotor of^this turbine is mounted on the same shaft as the rotor of the steam turbine 207. In the embodiment of Fig. l no governor and governor valve is providedin the gas turbine 215 for control of the combustion gases delivered thereto under pressure from the space within the casing 3. The two fluids, however, namely steam and combustion gases, under pressure of like degree or at equal pressures are delivered to the respective turbines for development of power upon the same shaft in cooperation with each other by expansion of the steam and the gases in the respective turbines. The speed of the shaft for a given load thereon will depend upon the combined eiort induced thereon by the two fluids.

In order to control the operation of the gas turbine 215 in proper relation to the operation of the steam turbine 207 in the embodiment of Fig.1 a differential device 220 is provided which comprises a vertically disposed cylinder withinv which is movableV a piston 221. To thespace above the piston 221 connection is established through the pipe 223 to the steam delivery pipe 205 so that the pressure of the generated steam substantially is brought upon the upper face of the piston 221.'

Similarly through pipe 225 connection is established between the space beneath the piston 221 and the gas delivery pipe 213 so that the pressure atthe under face of the piston is substantially that of the gases discharged from the space within the casing 3 of the steam generator. The size of the pipes and the connections and the length. thereof in Fig. 1 are not significant, the drawing being diagrammatic.` ln a practical embodiment the differential device 220 may be suitably located and the connections may be made so as to avoid undue pressure drop. Increase and decrease of the generated steam pressure relative to the gas pressure developed in the combustion chamber, therefore, is effective to move the piston 221 downwardly and upwardly.

rl`he piston rod 222 of the device 220 extends outwardlyl of the cylinder at the upper and lower ends thereof.` The upper end of the rod 222 is connected to valve disc 227 of a valve 229 connected in the steam delivery pipe 205. The lower end of rod 222 is connected to valve disc 231 of a valve 233 connected in the pipe 213 delivering the,

piston 221 eects closing movement of the steam con-V trol valve disc 227 and opening movement of the gas control valve disc 231. Downward movement of the piston 221 effects opening movement of the steam control valve disc 227 and closing movement of the gas control valve disc 231.

It will be understood, therefore, that `as the steam pressure rises in the steam generating tubes and in the delivery pipe 205 opening movement of the valve disc 227 will be eiected and correspondingly closing movement of the gas control valve disc 231. This operation will provide for increased ow of the steam through the pipe 205 to the turbine 207 and will decrease the ow of the combustion gases through the pipe 213 to the gas turbine 215. Such operation will tend to increase the speed of the steam turbine and the power output thereof. The speed of both turbines, however, is the same or in a predetermined relation as they drive the same shaft. The governor 209 controlling the supply of steam to the steam turbine tends to regulate the speed in response to variations in the load. If under a given load the speed is too low for the conditions of pressure which have just been stated the increased delivery of the steam through the valve 229 will tend to increase the speed to supply the power demand upon the turbines. Since the power delivered by the gas turbine is reduced because of the reduced gas supply thereto, the governor 209 will operate 1o permit the additional steam supplied through the valve 229 to ow through the governor valve 211 to the steam turbine 207 to maintain the speed and the power delivery of the combined turbine unit. The action of the dilferential device 220 upon the valve discs 227 and 231, however, will have been eiective for restoring the proper differential between the pressure of the steam flowing toward the steam turbine and the pressure of the combustien gases owngstwardthegas uubine` inerfeasne suchfow ofthe steam when-.tbe-fsteam-pressureincreases andcoucomitautly. reducing the owofe the gases;

If, onithercontrary, .the pressure of thesteanrowing fromthe tubes 65`falls relative. tothe pressure-of the gases owing. from. the` casing 3, .the pressure 'at-the under side` of the piston221- exceeds'- the pressure at the upper side of this piston and upward movementofl the piston rod 222 iseffectedwith closing movementof-` the valve disc. 227 and openingmovementof thevalve dise231'. By suchoperation the.. delivery of. thesteam from the steam generator. tothe. steam. turbine 207 is reduced and theV delivery of the gasesto the gas. 1:1 1rbine'2154 is in.- creased. Such throttling ofjthefsteam will increase. the pressure within the steam. generatingtubes 65 and Vsuch increased'flow of the. gasesdecrease the pressure within the combustion chamber so astomaintainthe desired relation between the pressure of then steam and'of the gases.` Such reduction .of thesteam delivered to the turbine'207`will tend to reduce .the speed ofthe steam turbille and-'thelpower delivered thereby. The increase. of the il'ow of the gasesto. the gas-turbine, however, will increasethe speed-thereof and of .thecombined unit to maintainfthe speed'thereofand the delivery of'power.

In the embodiment of Fig.v 1 the steam pressure responsive means 175 and thev diiferential device 220 and the'connections thereto are shown in simple diagrammatic form for ease of explanation of the principleof operation. InY order to avoid hunting and to. secure smoothnessof controlV and thedesired degree ofregulationitisdesirable or necessary to provide additional devices andrelays. In Fig. 2Y is'shown a system of controlsfor this purpose for effecting' control of. the supply of fuelA to the com.- bustion chamber and the delivery thereto of air at the requisitepressure. In Fig, 2 certain of theparts like those of Fig. l have reference numerals corresponding to those o .Fg, l.

In Fig, 2 the device 175 which is responsive to the pressure ofthe steamI is connectedY through pipe 17.7 to the pipe 205 whichV delivers` steamvfrom the steam gen? erator 1 tothe steam turbine 2.07 soV thatthe pressure of the generatedV steam is brought upon the uppery face of the: piston 176 of the device 175 in. opposition tospring 179 in the'same manner as 'shown in Fig. l. As in Fig. 1 the steamr pressure responsive device 175is operatively connected to the meansA for supplying the fuel to the burner 11 and to the means for supplying fuel to the internal. combustionengines which drive the compressor for delivering the compressed air to the combustion chamber. The. piston 176', however, instead of beingconnected directly tothe rod 181 as in Fig. l is connected through arelay about to be described, the rod 181 being, connected to two sets of fuel pumps'for.v controllingjthese pumps respectively to control the fuelv supplied to the combustion chamber and thefuel supplied'to the internal combustion engines;

Thepiston 176. is connected by piston rod 241 to a transverse bar 243 carried at. the lower end of the. piston rod 241 so that upward and downward movement of the piston 176eects upward and downward movement of the bar 243, Beneath the bar243 arearranged four valve boxes 245, 247, 249- and 251. The valve boxes 245and 249` are provided with seats so formed therein that valve discs 253 and 257 respectively therein both move upwardly to closed position of the valves. In the boxes 247 and 251 the seats are formed so that the valve discs 255 and 259 move downwardly to closed position. The stems 261, 263, 265 and 267 respectively of the valve discs 253, 255, 257 and 259 pass upwardly through suitable stuffing boxes (not shown) in the top walls of theV boxes 245, 247, 249 and 251 and through corresponding holes in the bar 243 in sliding relation to this bar.V These valve stems carry anges 269 at their upper ends and'beneath the oar 243 flanges 271. Between the'ilanges 269 ofthe valve stems 261, 265 and the bar 243 compression springs 273 are provided which bias these valve stems upwardly with respect to the bar 243 to bring the anges 271 thereof against the under face of this bar. Between the flanges 271 of the valve stems 263 and 267 and the under face of the bar 243 springs 275 are pro.- vided which bias the stems 263 and 267 downwardly relative to the bar to bring the flanges 2.69 into engagement with the upper vface of the bar 243.

In the position shown in Fig. 2, the'piston 176 `bemg `somewhat below the mid-position in the cylinder -175v bar 2.43. compressesthej. springs 275, to..clo se. the? valvesI 255 and 259, 'the;b'ar. 243..haviigmoved; somewhatfawayrfrom the flanges 269 ofthevalve stems 263 and267 'Hic springs 273` of the valve stems. 261` and 265,. however, havev expanded to move thefanges -1271- ofthese: valve stems upwardly into contact with the. bar243,v thefbar 243 acting as a unitwith the;anges 271 andthe-.valve stems 261 aud 265. and springs273V andrangesZSkto holdthevalves -253 and 257'downwardly from :their seats. Further downwardmovement ofthepiston 176-will effect further compression ofv the springs 275', furtherdowrrward movement ofthe stems .263.and267'not being pos.- sible. Such further. downward movement of thefstems 261, e .265',andof the .valves..253, 2517, however, .ispossible fr'omthe'poston Shfown in Eig.. 2.` Upnrupwardmver meut ofthey piston 1,76' from the.position of. Fig.2. the valves- 253 and 257'f1'rst will movefupwardl'y intolcoutaet with theirv seats and thereafter thefsprings1273'wii1be compressed by the bar 243. Concornit'antly upward movement ofthe bar 2.43 iirst'will eiect expansionof the springs275 until the. bar 243' makescontact with the flanges 269. ofthe stems 263,267.. Thereafter. the valves 255", 259 will' be ,lifted from their. seats.

An auxiliary control uid. such as-compressed air, may be deliveredv to' the relay through. pipe 277.. For the position of theA piston 176 as shown inv Fig...2. compressed controlair will flow through the openvalve 257 of the box 24,9andKA outwardly through the pipe.279 Connected by a'T'branch to boxesv249 and 251. Flow is prevented into the. box 251 since the valve 259.A is closed.`r` The;v pressure. delivered` through the pipe 279 will open; check valve 281 inthe head of an operating cylinder 283 tov bringA the. pressure. of' the. control air upon the piston 284 to whichthe rod 181 Iis connected. Such pressureintroduced above thepiston 2,84 will p ro. duce downward'movement thereof'to effect control of the fuel pumps as about to bey described. Such downf ward' movement of the piston 2841efects exhaust of the control air which is'. beneath the piston with `c lownward opening'movement' of vthe check valve. 2.85; This.. ex haust air passes through the pipe 2,87 connected by'a T branch to the boxes 245 and 2'47. The'valvez255 in the box- 24T is closed so that the dow into this box is pre.: vented. The valve 2,53 in the box 245, however, i `s ppen and the exhaust control airrnay be` discharged through this boxaud` through the exhaust pipe 289;"

When'upon reduction of thesteam` pressure the.pi sto n 176Vl in the-steam pressure responsivedevice 175't moves upwardly, being impelledfby the spring 179 the bar 24,3 moves upwardly andfcloses the'valves'253and 257Y and thereafter opens the valves 2,55' and 259l Thecompressed control' air'then passes vforn pipe 277 into the box247 througli'thevalve 255, now open,- and into.- the pipe 287, being prevented from` enteringjthe box 245 since: thek valve 253' is closed; This brin'gsthepressure upon'. the .check va1ve285-V to close this check'valye in the lower end ofthe cylinder 283'and upon cheek valve291 to open thisl checlevalve toadmit the control air. `to `the under side of. the piston 284, thereby to effect upward movement thereof and'of' the rod'lSl; As `the valve 2'57 is nowk closedv and the compressedcontrol air is prevented from entering' box 249'V and` thev air previously' admitted to the spacci above thepiston 2S4may pass out through the check valve 293`concomitantly with closing` of" the check valve 281' andl through pipe279'andthe valve 259 nowfopen lin the box 251110' be exhausted'through pipe 295;

`t will bev apparent, therefore, that the rod 18.1 is moved downwardly with increase ofthe steam pressure exerted upon the'upper faceof thea piston y176 and is moved upwardly upon reduction' ofthis pressure in a manner: similar to the'rod 181, Fig: 1 but with a diier` ence off action which'will be-descri'bedhereinafter.'

In'the'embodiment'of Fig. 2'the rod-r181v is connected by abell crank lever 305 to a-lr`orizontallyextending rod 307 which is connected to means forcontrollingthev discharge of the' fuel feed pumps'- 309W the pistons of which are actuated from a cam shaft 311 having cams 312 thereon for mechanically engaging'in4 succession' the piston rods of thesepumps. Thehorizontally extending rod 397 valsois. continued to'the left` for actuatingfthe. means for control-lingthe delivery offue'lr from the .pumps 3^13ffor feeding the fuelv to the' burner'l'l' of thestearn' generator 1. The pistons of thesev pumps are actuated by cams'315 carried on cam shaftt3161 The shafts 311 and 316 may be'driven hby any `suitable means.

The 1fuel discharge from the pumps 309 is carried through the pipes 317 to cylinders 319, 321, 323 and 325 of internal combustion engines the pistons of Awhich are directly connected to the pistons of air compressors 327, 329, 331, 333. The compressor 327 v1s utilized for compressing the air for combustion of the fuel in the internal combustion engine cylinders, being delivered thereto through the pipe 335. The comprcssor cylinder 329 is a low pressure cylinder of a threestage compressor, the air compressed therein being delivered through pipe 337 to the intermediate stage cylinder 331. The air compressed in the intermediate stage cylinder 331 is delivered through the pipe 338 to the high pressure cylinder 333 from which it isdischarged through pipe 339 to the burner housing 340 of the steam generator 1 for delivery within the casing 3 thereof for combustion in the combustion chamber of the fuel supplied to the burner 11.

In the embodiment of Fig. 2, if the pressure of the steam generated in the steam generating tubes and applied upon the upper face of the piston 176 increases the supply of the fuel both to the burner 11 and to the internal combustion engines driving the air compressor is reduced, thereby to reduce both fuel and air to reduce the combustion of fuel and the release of heat in the combustion chamber. If, on the other hand, the steam pres- ,sure decreases upward movement of the rod 181 is effected and the supply of fuel to the burner 11 and to the engines 319, 321, 323, 325 is increased to increase simultaneously the supply of fuel to the burner and the delivery of air for the combustion of this fuel, thereby to increase the` steam pressure to restore it to the desired pressure. The relay device shown within the dotted rectangle A which includes the bar 243 and the valve boxes 245, 247, 249, 251 and the valves therein operating in the manner described is effective to produce movement of the piston 284 and therefore of the rod 181 controlling the pumps 309 and 313 with sufficient lag behind the action of the piston 176 to avoid hunting. To this end the adjustment of the valves 253, 255, 257 and 259 with respect to their seats and in relation to the bar 243 and the anges 269, 271 is such that the valves 253, 257, for example, close before the valves 255, 259 open and vice versa so that the compressed control air is locked in the cylinder 283 at bothsides of the piston 284 and the rod 181 is held in the position to which it has been moved. When, however, the steam pressure in the steam 'generator is restored to the desired pressure opposite movement of the piston 176 in response thereto will become effective to operate the relay A to reverse the movement of rods 181 and 307 to correspondingly modify the supply of fuel and delivery of the compressed air. A smooth control operation thereby is secured of the device for supplying fuel to the burner and for operation of the compressors to supply the combustion air to the combustion chamber in accordance with the amount of fuel delivered to the burner in response to variations of the steam pressure.V

In Fig. 2 also is shown the differential device 220 correspending to that of Fig. 1. The space at the upper side of the piston 221 of the differential device 220 is connected kthrough pipes 223 and 177 to the steam pipe 205 through which the steam from the steam generator 1 is delivered to the steam turbine 207. The space at the under side of the piston 221 is connected through the pipe 225 to the pipe 213 delivering the combustion gases from within the casing 3 of the steam generator to the gas turbine 215. Within the rectangle B drawn in dotted outline in Fig. 2 is shown a relay structure associated with the differential device 220 corresponding to that shown within the rectangle A associated with the device 175 which is responsive to the steam pressure. The parts within the rectangle B bear reference numerals corresponding to those within the rectangle A but different therefrom bv 100. Thus, the cross bar 343 associated with the Adifferential device 220 and the valves 353, 355, 357 and 359 and the respective valve stems and springs function in the same manner as do the parts within the rectangle A when the bar 343 is moved bv rod 222 upon movement of piston 221 of the device 220. The compressed control air supplied through the pipe 377undex the control of the relav device B may be delivered through the pines 379and 387 to the spaces in the two cylinders 383 and V393 respectively above and below the pistons 384 and 394in-these cylinders. Thesecvlinders are provided with check valves in the heads therein arranged and functioning the same as do the check valves of the cylinder 283 to bring the pressure of the compressed control air simultaneously upon the upper side of the pistons 384 and 394 and to exhaust this pressure therefrom and to bring the pressure upon the lower side of these pistons and to exhaust the pressure therefrom upon operation of the valves 353, 355, 357 and 359 of the device associated with the differential device 220. Both pistons 384 and 394, therefore, are adapted to move downwardly and upwardly in their respective cylinders concomitantly respectively with increase and decrease in the pressure of the steam relative to the pressure of the combustion gases to which the differential device is responsive.

In the apparatus of Fig. 2 the pressure of the steam is intended to be controlled so as to be somewhat less than the pressure of the combustion gases, this difference being measured by the spring 397 bearing on the lower head of the cylinder of the device 220 and upon a flange 398 fastened upon the piston rod 222, thus to bias the piston rod downwardly. Increase in the pressure of the steam relative to the gas pressure aided by the spring 397 will move the bar 343 downwardly to a position such as is shown in Fig. 2 to effect delivery of the compressed control air from pipe 377 through the pipe 379 to move the pistons 384 and 394 downwardly and to eX- haust the pressure beneath these pistons through pipe 387 to the discharge pipe 389. Such downward movement of the piston 394 is effective through the piston rod 399 connected to the valve disc 227` in valve 229 inserted in the steampipe 205 to move this valve disc in the direction away from its seat thereby to increase the delivery of steam Vto the turbine 207. Similarly, downward movement of the piston 394 connected by the rod 401 to the valve disc 231 of valve 233y inserted in the pipe 213 delivering the combustion gases to the gas turbine 215 effects closing movement of the disc 231 to decrease the ow of the gases to the turbine 215. Conversely, decrease of the steam pressure relative to the gas pressure will effect upward movement of the piston 221 of the differential device 220 resulting in upward movement of the pistons 384 and 394 to effect respectively closing and opening movement of the valve discs 227 and 231. Such movement will reduce the ow of the steam to the steam turbine 207, thereby reducing the outow of steam from the steam generating tubes of the steam generator 1 to allow the pressure therein to build up and correspondingly will increase the ow of the gases from the combustion space within the casing 3 to reduce the pressure of the combustion gases within this space. Thus, the differential device 220 is effective to control the pressure of the steam generated in the steam generator 1 and of the combustion gases produced in .its

combustion chamber to maintain the difference between these two pressures substantially constant, the pressure of the steam generated relative to the atmosphericpressure being maintained substantially constant in the conventional manner by the control device 175 which functions through the relay device of the rectangle A controlling the fuel supplies to the burner 11 and to the internal combustion engines 319, 321, 323, 325 driving the compressors to increase and decrease both the fuel and the compressed air supplied to the combustion chamber responsive to decrease and increase of the steam pressure.

Similarly to the embodiment of Fig. 1 the speed of the combined steam turbine-gas turbine unit is controlled by governor 209 of the steam turbine operating the governor valve 211. vIn the embodiment of Fig. 2, as in Fig. l, no governor is utilized for control of the gases to the gas turbine, the operation of these turbines with respect to control of the speed and in response to variations in the load being effected in the same manner as described in connection with Fig. 1. It will be understood where the equipressure steam generator of the invention is combined with steam utilizing and gas utilizing prime movers, such as gas and steam turbines, that the steam generator may be located in close proximity to the turbines so that the pipes conducting the steam and the gases to these turbines may be short. Moreover, because of the shortness of the connecting pipes it is possible to make these pipes of large diameter without undue cost. The pressure drop developed in these pipes producing ow of the steam and the gas therethrough, therefore, may be quite small. Pressures of the steam and of the gas as delivered respectively to the steam and gas turbines thus may be not substantially less than the pressures of the steam generated in the steam generator and of thegases. as discharged -fromy the casing 3. Irtthe' drawingsthe lengthsof-theconnectingrpipes and the diameters thereof 'aresnotsignilicann vthese pipes and the arrangement of several parts of 'the' apparatus being shown diagrammatically for clearness and to show' the principle of operation and of. control ofthe steam generator and thefpower producing lplant of the invention.

Inthe embodiment ofFig. l hand controlled valves 19 and 123 are shown respectivelyin fuel supply-line17 and the air delivery pipe 2,1; It will be understood that the steam generator may be operated by handv operation of the valves 19 and23 togcneratesteam by the heat of the fuel'burnedin' the combustion chamber so that the combustion gases'may be produced atj a pressure of the'same degree as the steam pressure. Such, operation may be accomplished with'.v the' apparatus'. of Fig. 1 b-y blocking open the-valvedisc's 18'6r and 192'Lrespectively of the fuel supply valve 135v and the fuel supplyvalve 191. The compressor 203 then may be controlled by the hand operated valve 20'2 in thepipe-lSfS supplying fuel to the internal Vcombustion engine 197.

In carrying out the equipressure method by hand operation, ifthe pressure of the steam in the steam generating tubes 65 increases relative to the pressure of the gases within the casing 3, thevalve 19Amay be throttled to reduce the supply of fueltothe burner 11 suiciently to decrease the heat release in the combustion chamber thereby to' reduce the pressure Vof the steam tothe desired degree. Concomitantly with such rise of steam pressure relative to the pressure of the combustion gases the supply ofcompressed air. to the combustion chamber'either may bepkeptrconstant by hand operation of the valve 23 to allow the steam pressure to become reduced again and to restore the'e'quipressurerelation or thevalve 23may be operated to increase thedelivery of the compressed air to the combustionchamber in orderA to increase the pressure of the gases within' the casing 3 and thereby reduce the 'dilerence between the'steampressure'and the gas pres'- sure. Conversely, upon reduction of the pressure .of the generated steam'the'valve 19m'aybe operatedto increase thesupply of' fuel t'o the burner. 11" and the valve 23 may be operated to maintainthe pressure of the combustion gases substantially ,constant or may bethrottled'to reduce the delivery of the compressed air to the combustion chamber, thereby to reduce the pressure. of the. gases within the casing 3 to're'sto're the desired diiference between steam pressure and the pressure of the combustion gases.

Themethod of equipressurefsteam generation may also becarried'out if desiredby utilizin'g'a conventional de@ vice, such as the device1175'of Fig. l which is responsive to the steam pressure, for controlling the. supply of fuel to burner I1 to decreaseand'incrcase the supply of. this fuel as th'es'team pressure increases and decreases; The delivery ofthe air' tothe combustion chamber then'may be controlle'dbyhandoperation 'of the valve 23` so as to cause the'pressur'e of the combustion gases'tofollow the variations (of the vsteam pressure, that is, to. increase the deliveryof'the air if the steam pressure has'risen and to decrease the supplyof la'irif the s tearnppressure has fallen; On the'o'ther hand, the device 175'responsive vto the'steam pressure may be connected to the a'ir Vdelivery control device vto increase and decrease delivery of the compressed air'to the combustion chamber in responsetoincrease and decrease ofthe steam pressure, thefuel supply being respectively reduced and increasedby operation ofthe vvalve 19fby hand. p Y

In each of the embodiment/sV shown in the drawings safety valves may be utilized both for the release of the pressure within the casing 3 as well as of the steam pressure within the steam generating and `superheater `structure. Such valves may be'connected, for example, respectively to the gas discharge pipe i1 and to the steam discharge pipe 73v of Fig. l and to the corresponding dis.- charge pipes 213 and ZGS'Of'Fig. 2, or these safety valves may be connected otherwise to the gas and steam spaces of the generator 1.or of the pipes'leading to the prime movers 2'1'5 and 207 to effectV discharge therethrough of gasor steam upon the development'of excessive pressures.

Preferably, in the equipressure power plant of the invention the liquid to be vaporized is circulated through the vapor generating tube 65 under forced circulation. While in the embodiment shown diagrammatically in Fig. l the path of this circulation is represented as a single passage in succession through Athe various sections ofthe heating surface, thatfis, through theeconomizer, the sev-V 10 eral vapor generating tubes .in succession andfthrough-the superheater, othertypes vof vapor-generatingstructuresmay be utilized in which forced circulationof the liquid within the structure is provided, the Vapor which may be ySuperf heated, if desired, being` deliveredat the outlet'off the tube, that is, through the discharge pipe 73.

Within the scope ofthe invention also the structures which have been described in connectionwith theY draws ings for the generation of steam at high pressure and. for the development of power therefrom and for the produc,- tion of combustion gases at high pressure and temperature and the development of power therefrom may be utilized for the generation and utilization of vapor from other liquids such as mercuryliquid hydrocarbons, etc. The apparatus for andthe method of operating the power plant of the invention to maintain equipressure conditions not only in theV generation of vapor and gas but also. in the delivery of these fluids to respective prime movers lend themselves to the heatingA of a widevariety of vaporizable liquids as well as lgaseous fluids. Various adaptationstand modifications of the structure different from those def scribed and shownin the drawings may be utilized for-the generation of vapor and the production oflcomb'ustion gases at aV pressure -ofthe samedegree as the pressure of the generated vapor and for control of the operation of the prime movers to maintain the desired predetermined relation of the pressures of vapor and gas.. Such variations .and modifications are intended to be comprehended within the scope of the appended claims.

I claim:

l. A powergeneratingplant for developing; power from two fluid` pressure mediav under pressures substantially above atmospheric pressure which comprises a pair of prime movers respectively adapted to utilize said fluid pressure media 'to developjpowerI therefrom, means respecf tively. connected to said'prime movers for delivering the respective.'uid pressure media respectively at said pressures to said prime rnovers, meansrespectively operatively connected to saidv two delivery means for controlling delivery ofthe respective uids to said prime movers, and means responsive to variations from apredetermined diff ference between'. the pressures'of said fluids and operatively connected to said two delivery control means for operating said two control means to control said deliveries so as` to maintain substantially constant said predetermineddiiference between the Vpressures of said uid prese sure media.

2.' A power generatingv plant for developing power from two fluid pressure media under pressures substan-A tially vabove atmospheric' pressure which comprises a pair of-'prime movers respectively adapted toutilize said uid pressure media to" develop power therefrom, means-respectively 'connected to said prime movers for delivering the respective uid pressuremedia respectivelyv at said pressures to said primemovers, means respectively roperatively connected to said'twoV delivery means for controlling delivery of the: respective uids to said prime movers, and means responsive to.variationsrfrom a predetermined'difference' between'the pressures'of said uids and operatively connected to said two delivery control means for operatingsaid two'control means to control said deliveries so vthat respectively upon increase and def crease of the pressure of a given oneof said uid `pressure media relative .to the pressure of the other uid pressure medium the deliveryiof. said `given uid .pressure medium to the corresponding prime mover is increased and decreased" and the delivery of the other uid pressure medium to the other prime mover isdecreased and increased.

3. A power generating plant. for developing power from two `liuidpressure media under pressures substantiallyabove atmospheric pressure whichcomprises a pair of prime movers respectively adapted 'to utilize said fluid pressure media to develop'power therefrom, means respectively adapted for generating said duid pressure ,media at said pressuresthereof substantially above atmospheric pressure, means respectively connecting said two generating means to said prime movers for .delivery of the respective` fluid pressure media to said prime movers for developing power therefrom, means respectively operatively connectedto said two delivery means for controllingrespectively the delivery of said fluid pressure media from said two generating means. to said prime movers, and` meansresponsive'to variationsfrom alpredetermined ference between the pressures ofsaidtuid pressure media 11 and operatively connected to said two delivery control means for operating said two delivery control means to control delivery of said fluid pressure media to said prime movers so that respectively yupon increase and decrease of the pressure of a given one of said fluid pressure media relative to the pressure of the other fiuid pressure medium the delivery of said given uid pressure medium to ,the corresponding prime mover is increased and decreased and the delivery of said other fiuid pressure medium to the other prime mover is decreased and increased.

4. A power generating plant for developing power from two fluid pressure media under pressures substantially above atmospheric pressure which comprises a casing providing a chamber and constructed to confine within said chamber a gaseous fluid at a pressure elevated substantially above atmospheric pressure, an element for confining therein an expansible fluid at a pressure substantially above atmospheric pressure and for transferring to said fluid therein heat received by said element, means connected to said chamber for producing within said chamber said gaseous uid at said elevated pressure in heat transferring relation to said element and at a temperature elevated so as to effect transfer of heat to said element and to said fluid therein, a prime mover connected by uid conveying means to said element to receive therefrom said heated expansible uid at said elevated pressure to develop power by expansion of said expansible uid in said prime mover, a gas utilizing prime mover connected by gas conveying means to said chamber to receive therefrom said gaseous fluid at said elevated pressure for utilization in said gas utilizing prime mover to develop power therefrom, means connected to said iiuid conveying means for controlling delivery of said expansible'ruid from said element to said prime mover connected to said element, means connected to said gas conveying means for controlling delivery of said gaseous uid from said chamber to said gas utilizing prime mover, and means responsive to variations from a predetermined difference between the pressure of said expansible fluid and the pressure of said gaseous fluid and operatively connected to said means for controlling delivery of said eX- pansible uid and to said means for controlling delivery of said gaseous fluid respectively to said prime movers for operating said two control means to control said deliveries so that respectively upon increase and decrease of the pressure of a given one of said fluids relative to the pressure of the other fluid the delivery of said given fluid to the corresponding prime mover is increased and decreased and the delivery of the other fluid to the other prime mover is decreased and increased.

5. A power generating plant for developing power from two uid pressure media under pressures substantially above atmospheric pressure which comprises a casing enclosing a combustion chamber, a vapor generating element within said chamber for generating vapor at a pressure elevated substantially above atmospheric pressure. said casing being constructed to confine the combustion gases therein at a pressure elevated substantially above atmospheric pressure and in heat transferring relation to said element, means for supplying fue] to said combustion chamber for combustion therein, means for delivering a combustion supporting gas into said chamber against the pressure therein for support of the combustion at said elevated pressure of the fuel sup plied to said chamber to generate the vapor at said elevated pressure in said element,V a vapor utilizing prime mover connected by a vapor conveying conduitto said vapor generating` element to receive therefrom said generated vapor substantially at said elevated pressure for utilization in said prime mover to develop power therefrom, a gas utilizing prime mover connected by a gas conveying conduit to said combustion chamber to receive therefrom lsaid combustion gases substantially at said elevated pressure for utilization in said gas prime mover to develop power therefrom, means connected to said vapor conveying conduit for controlling the delivery of said vapor from said'vapor generating element to said vapor utilizing prime mover, means connected to said gas conveying conduit for controlling the delivery of the combustion gases from said combustion chamber to said gas utilizing prime mover, and means responsive to variations from a predeterminedy difference between the pressure of the Ygenerated vapor and the pressure of the combustion gases and operatively connected to said means avoas for controlling the delivery of said vapor and to said means for controlling `the delivery of said combustion gases respectively to said prime movers for operating said two control means to vary the delivery of the vapor inversely with respect to the delivery of the gas and directly with variation of the pressure of the vapor relativel to the pressure of the gas so as to maintain substantially constant said predetermined difference between the pressure of said vapor delivered to said vapor utilizing prime mover and the pressure of said combustion gases delivered to said gas utilizing prime mover.

6. A power generating plant for developing power from two fluid pressure media under pressures substantially above atmospheric pressure which comprises a casing enclosing a combustion chamber, a vapor generating element within said chamber for generating vapor at a pressure elevated substantially above atmospheric pressure, said casing being constructed to confine the combustion gases therein at a pressure elevated substantially above atmospheric pressure and in heat transferring relation to said element, means for supplying fuel to said combustion chamber for combustion therein, means for delivering a combustion supporting gas into said chamber against the pressure therein for support of the combustion at said elevated pressure of the fuel supplied to said chamber to generate the vapor at said elevated pressure in said element, a vapor utilizing prime mover connected by a vapor conveying conduit to said vapor generating element to receive therefrom said generated vapor substantially at said elevated pressure for utilization in said prime mover to develop power therefrom, a gas utilizing prime mover connected by a gas conveying conduit to said combustion chamber to receive therefrom said combustion gases substantially at said elevated pressure for utilization in said gas prime mover to develop power therefrom, means connected to said vapor conveying conduit for controlling the delivery of said vapor from said vapor generating element to said vapor utilizing prime mover, means connected to said gas conveying conduit for controlling the delivery of the combustion gases from said combustion chamber to said gas utilizing prime mover, and means responsive to variations from a predetermined difference between the pressure of the generated vapor and the pressure of the combustion gases and operatively connected to said means for controlling the delivery of said vapor and to said means for controlling the delivery of said combustion gases respectively to said prime movers for operating said two control means to control said deliveries so that respectively upon increase and decrease of the pressure of a given one of said fluids relative to the pressure of the other uid the delivery of said given fluid to the corresponding prime mover is increased and decreased and the delivery of said other fluid to the other prime mover is decreased and increased.

7. A power generating plant as defined in claim 5, in which said means responsive to variations from apredetermined difference between the pressure of the generated vapor and the pressure of the combustion gases is adapted to maintain said vapor pressure and said combustion gas pressure substantially equal.

8. A power generating plant as defined in claim 5, in which said means responsive to variations from a predetermined difference between the pressure of said generated vapor and the pressure of said combustion gases comprises means for preventing hunting of said means for controlling delivery of vapor and of said means for controlling delivery of said combustion gases respectively to said prime movers.

9. A power generating plant as defined in claim. 5, which comprises means responsive to variations in the pressure of the vapor delivered to said vapor utilizing prime mover and operatively connected to said means for supplying fuel to said combustion chamber and operatively connected to said means for delivering a combustion supporting gas into said chamber for controlling the supply of fuel and the delivery of the combustion supporting gas to said chamber to control the pressure of the vapor generated in said vapor generating element.

l0. A power generating plant as defined in claim 9, in which said means responsive to variations in the pressure of the vapor delivered to said vapor utilizing prime mover comprises means for preventing hunting operation of said means for supplying fuel to said combustion chamber and of said means for delivering a combustion-sup-- porting gas into said chamber.

1l. A power generating plant as dened in claim 5, in which said means responsive to variations from said predetermined pressure dierence comprises a relay responsive to said variations from said predetermined direrence between the pressure of generated vapor and the pressure of the combustion gases and operatively connected to said means for controlling the delivery of said vapor and to said means for controlling the delivery of said combustion gases respectively to said prime movers for controlling said deliveries so as to maintain said predetermined direrence substantially constant.

12. A power generating plant as deiined in claim 5, which comprises a relay responsive to variations in the pressure of the vapor delivered to said vapor utilizing prime mover, and control means actuated by said relay and operatively connected to said means for supplying fuel to said combustion chamber and operatively connected to said means for delivering a combustion supporting gas into said chamber for controlling the supply of fuel and the delivery of the said combustion supporting gas to said chamber to control the pressure of vapor generated in said vapor generating element.

13. A power generating plant as dened in claim 5, in which said means for delivering a combustion supporting gas to said combustion chamber comprises a compressor for compressing said combustion supporting gas to the pressure within said combustion chamber for delivery thereto, a fuel utilizing prime mover operatively connected to said compressor to drive said compressor, means for feeding fuel to said fuel utilizing prime mover for operation thereof to drive said compressor, and means responsive to variations in the pressure of the vapor delivered to said vapor utilizing prime mover and operativly connected to said means for supplying fuel to said combustion chamber and operatively connected to said means for feeding fuel to said fuel utilizing prime mover for controlling the supply of fuel to said combustion chamber and for controlling the feeding of the fuel to said fuel utilizing prime mover to control the delivery of said combustion supporting gas to said combustion chamber, thereby to control the pressure of the generated vapor.

14. A power generating plant as dened in claim 5, in which said prime movers are operatively connected together to maintain their respective speeds in constant relation to each other, and a governor for one of said prime movers responsive to the speed thereof and controlling the ow of the uid thereto to control in cooperation with said means responsive to variations from said predetermined diierence between the pressure of said vapor and the pressure of said combustion gases the speed and the operation of both said prime movers.

15. A power generating plant as defined in claim 5, in which said means responsive to variations from said predetermined pressure difference comprises a member responsive to said pressure difference and moved respectively in a given direction and in an opposed direction upon increase and decrease of the pressure of a given one of said iiuids relative to the pressure of the other uid, means operatively connecting said member to said vapor delivery controlling means and to said combustion gas delivery controlling means for eiecting operation of said two controlling means to respective given control positions and to respective opposed control positions respectively upon movement of said member in said given direction to a predetermined forward position and upon movement of said member in said opposed direction to a predetermined opposed position spaced from said forward position ot' said member, and means operatively connected to said connecting means for etfecting actuation of said connecting means to prevent movement of said vapor delivery controlling means and said combustion gas delivery controlling means in positions of said memper intermediate between said predetermined positions thereof.

16. A power generating plant for developing power from two iuids at respective pressures which comprises a pair of prime movers respectively capable of utilizing said tluids at the respective pressures to develop power therefrom, means respectively connected to sald prime movers for delivering said fluids respectively at said pressures to the respective prime movers, and control means responsive to variations in the pressures of said iluids relative to each other and operatively connected to said two delivery means for controlling said deliveries of said fluids so as to increase the delivery of a given one of said uids to the corresponding prime mover concomltantly with decreasing the delivery of the other uid to the other prime mover upon increase of the pressure of said given uid relative to the pressure of said other liuid and to decrease the delivery of said given uid to the corresponding prime mover concomitantly with increasing the delivery of the other duid to the other prime mover upon decrease of the pressure of said given fluid relative to the pressure of said other iluid.

17. A power generating plant for developing power from a vapor and from a gas at respective pressures which comprises a prime mover capable of utilizing said vapor at said vapor pressure to develop power therefrom, a prime mover capable of utilizing said gas at said gas pressure to develop power therefrom, means respectively connected to said prime movers for delivering said vapor and said gas at the respective pressures to the respective prime movers, and control means responsive to variations in the pressures of said vapor and of said gas with respect to each other and operatively connected to said two delivery means for controlling said deliveries of said vapor and of said gas to increase the delivery of said vapor to said vapor utilizing prime mover concomitantly with decreasing the delivery of said gas to said gas utilizing prime mover upon increase of the pressure of said vapor relative to the pressure of said gas and for decreasing the delivery of said vapor to said vapor utilizing prime mover concomitantly with increasing the delivery of said gas to said gas utilizing prime mover upon decrease of the pressure of said vapor relative to the pressure of said gas.

References Cited in the tile of this patent UNITED STATES PATENTS Germany Aug. 29, 1919 

